2506.10.00 | 10 | Sands (other than natural) containing by weight 95 percent or more of silica and not more than 0.6 percent of oxide of iron | t | | | |
2506.20.00 | 10 | Crude or roughly trimmed | t | | | |
2507.00.00 | 00 | Kaolin and other kaolinic clays, whether or not calcined | t | Free | | $2.46/t |
2508 | | Other clays (not including expanded clays of heading 6806), andalusite, kyanite and sillimanite, whether or not calcined; mullite; chamotte or dinas earths: | | | | |
2508.30.00 | 00 | Fire-clay | t | Free | | $1.97/t |
2508.40.01 | | Other clays | | Free | | $1.97/t |
2508.40.01 | 10 | Common blue clay and other ball clays | t | | | |
2508.40.01 | 20 | Decolorizing earths and fuller's earth | t | | | |
2508.50.00 | 00 | Andalusite, kyanite and sillimanite | t | Free | | Free |
2508.60.00 | 00 | Mullite | t | Free | | 30% |
2509.00 | | Chalk: | | | | |
2510 | | Natural calcium phosphates, natural aluminum calcium phosphates and phosphatic chalk: | | | | |
2511 | | Natural barium sulfate (barytes); natural barium carbonate (witherite), whether or not calcined, other than barium oxide of heading 2816: | | | | |
2511.10 | | Natural barium sulfate (barytes): | | | | |
2511.20.00 | 00 | Natural barium carbonate (witherite) | kg | Free | | 30% |
2512.00.00 | 00 | Siliceous fossil meals (for example, kieselguhr, tripolite and diatomite) and similar siliceous earths, whether or not calcined, of an apparent specific gravity of 1 or less | t | Free | | Free |
2513 | | Pumice; emery; natural corundum, natural garnet and other natural abrasives, whether or not heat-treated: | | | | |
2513.10.00 | 10 | Crude or in irregular pieces, including crushed pumice | kg | | | |
2513.20 | | Emery, natural corundum, natural garnet and other natural abrasives: | | | | |
2513.20.10 | 00 | Crude or in irregular pieces | kg | Free | | Free |
2514.00.00 | 00 | Slate, whether or not roughly trimmed or merely cut, by sawing or otherwise, into blocks or slabs of a rectangular (including square) shape | t | Free | | 25% |
2515 | | Marble, travertine and other calcareous monumental or building stone of an apparent specific gravity of 2.5 or more, and alabaster, whether or not roughly trimmed or merely cut, by sawing or otherwise, into blocks or slabs of a rectangular (including square) shape: | | | | |
2515.11.00 | 00 | Marble and travertine: | | | | |
2515.11.00 | 00 | Crude or roughly trimmed | m3 t | Free | | $22.95/m3 |
2515.12 | | Merely cut, by sawing or otherwise, into blocks or slabs of a rectangular (including square) shape: | | | | |